(1) Field of the Invention
The invention relates to a method for playing images, and more particularly, to a method for playing images, which method can still smoothly play digital images during playing the video data on a disc through a disc player, if the read DVD video data are not correct.
(2) Description of the Prior Art
The full name of the DVD is “Digital Versatile Disc” which is developed based on CD-ROM. The sizes of both are the same, but because the track pitches of DVD and the spot size on the recording surface are smaller, and the coding rate of DVD data format is higher, the storage capacity is much bigger. The DVD can be used to store various digital files, for example, audios, videos and computer file data. At the very beginning, the DVD was also called “Digital Video Disc”, and then now is called “Digital Versatile Disc”.
In fact, specifications and applications of the DVD can be widely used, so it is difficult to have a common characteristic. The followings are considered as basic characteristics of the DVD at the very beginning:    1. The video signal uses MPEG 2 compression technology, quality of which is better than that of laser disc, VHS video tape, and the present VCD.    2. The audio signal uses AC-3 of Dobby stereo technology.    3. Single disc can store a whole movie including the video signals and audio signals.    4. In order to match the aforesaid terms, the capacity of single disc is at least 4.7 giga byte which is seven times than that of the CD.    5. Size of the DVD is the same as that of the CD. i.e., 12 cm diameter, and 1.2 mm thick, so that the DVD is compatible, that is, DVD player can read the present various CDs.
Nowadays, the DVD is getting more and more popular, and the data on the DVD have an Error Detection Code (EDC), to judge if the read DVD data are correct or not. Please refer to FIG. 1 which shows a flowchart of the method for playing images in the prior art. On the market, there are disc players which are installed in personal computers or in notebook computers. When DVD video data are read, if there is a mistake checked out by EDC, the disc players will continue trying until correct DVD video data are read.
The method for playing digital movies in the prior art includes the steps of: putting a disc into a disc player (s102); judging if the disc has the DVD video data (s104); reading the DVD video data from a file holder of the DVD video data, if the disc has the DVD video data (s106); stopping the operation, if the disc does not have the DVD video data, and waiting for next operation command (s108); judging if the read DVD video data are correct, after the DVD video data are read (s110), wherein the judgment is made according to the EDC contained in the DVD format data; outputting the DVD video data to the computer if the read DVD data are correct, to let a playing software of the computer play (s112); the disc player continuing reading (that is, repeating the step s112) until the correct video data are read, if the read DVD video data are not correct.
At that time, the playing software of the computer will wait for the DVD video data outputted from the disc player, while the video frame that user can see is still, and control panel of the playing software cannot make any response, because of waiting for the DVD video data, which cause a problem that is very similar to “a shutdown condition”.